Cremer, Helmuth, De Donder, Philippe and Rodriguez, Frank (2005) Access Pricing in the Postal Sector. Results from a Model with Bypass and Customer Direct Access. In: Regulatory and Economics Challenges in the Postal and Delivery Sector Crew, Michael A. and Kleindorfer, Paul R. (eds.) Springer. Series “Topics in Regulatory Economics and Policy” pp. 163-187. ISBN 978-1-4020-7972-6